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Python

Posted by Shiming Zhang
Shiming Zhang
829 Points

Why doesn't my service charge work?

<p>def calculate_price(number_of_tickets):
    return (number_of_tickets * TICKET_PRICE) + SERVICE_CHARGE

while tickets_remaining >= 1:
    print("There are {} tickets remaining.  ".format(tickets_remaining))
    name = input("What is your name?   ")
    num_tickets = input("How many tickets would you like, {}?  ".format(name))
    try:
        num_tickets = int(num_tickets)
        if num_tickets >= tickets_remaining:
            raise ValueError("There are only {} tickets remaining.".format(ticket_remaining))
    except ValueError as err:
        print("Oh no, we ran into an issue. Please try again.")
    else:
        amount_due = calculate_price(num_tickets)
        print("The total due is ${}  ".format(amount_due))
        should_proceed = input("Do you want to proceed?  Y/N    ")
        if should_proceed.lower() == "y":
            print("SOLD!")
            tickets_remaining -= num_tickets
        else:
            print("Thank you, {}".format(name))
print("Sorry the tickets are all sold out. :(")</p>
          ```

1 Answer

KRIS NIKOLAISEN
KRIS NIKOLAISEN
54,974 Points

I'm assuming the paragraph tags are part of your post here and not your Python code. I'm also unsure of what you mean by the service charge not working. If you could provide clarification that would be great. I did find a few things to address however:

1) There are several variable declarations missing. For example:

tickets_remaining = 100
TICKET_PRICE = 10
SERVICE_CHARGE = 2

Did you post all of your code?

2) By including equal to here you will never be able to purchase all the tickets:

if num_tickets >= tickets_remaining:

To test try the total number of tickets as the first purchase. The condition should just be greater than.

3) There is a typo here:

raise ValueError("There are only {} tickets remaining.".format(ticket_remaining))

which results in:

NameError: name 'ticket_remaining' is not defined.

The previously used variable is tickets_remaining with an s

Shiming Zhang
Shiming Zhang
829 Points

Yes, I didn't post all my code. For me, if I input the number of tickets, it will just feedback the num_tickets * tickets_remaining, without the service charge. I feel a little bit strange, so I ask this question. Thanks for your help.